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We tend to think of wasps as unpleasant animals because of the painful stings they can impart when feeling defensive. But these wasps have nothing on the nastiness of their parasitic cousins, which sting their victims (usually an insect) prior to laying eggs on them, after which the larvae consume the victim alive—the wasps' venom can induce anything from paralysis to behavioral changes in order to make that meal go smoothly. That's made a number of species very useful for pest control, but one specific genus of parasitic wasp, called Nasonia, may be getting an additional role: lab rat.

A new paper describes the completion of the genomes of four Nasonia species, and details why they make a great species for biologists to study. For starters, genetics is easy. Females, like humans, carry two copies of every chromosome. But males develop from unfertilized eggs, which only carry one of each. With only one copy, even recessive mutations will be easy to identify and characterize.

The four species don't interbreed in the wild, but that turns out to be because of a bacterial infection (more on the Wolbachia bacteria for the curious). Give them antibiotics, and the species can interbreed, allowing researchers to use genetics to track all sorts of interesting behaviors. Already, researchers have identified areas of the genome that appear to control things like female mate preferences, male courtship behavior, and what species they choose to paralyze.

The genome itself is fairly typical for insects, but has a few interesting twists. For example, the Wolbachia bacteria mentioned above contributed genes to the species in the distant past, as did pox viruses that infect it. Many of these genes now seem to be involved in interactions among the wasps' cells. There are 445 genes that Nasonia shares with humans but not its fellow insect Drosophila, including a full set of DNA methylation proteins, which regulate epigenetic inheritance. The researchers also identified nearly 80 proteins that may produce venom molecules.

Nasonia is unlikely to displace common lab organisms, but it may be very useful for some particular areas of study, like speciation, venom production, and DNA methylation. In the past, it might have taken decades to develop the genetic tools needed to use this species, but the ability to complete genomes in a matter of months has completely changed the equation.